Officials discover what turned Venice’s Grand Canal green

For days, Venetians have wondered why part of their city’s famous Grand Canal turned such a bright green.

On Monday, authorities had an answer: Test samples of the water confirmed that the canal’s bright new hue was caused by fluorescein, a chemical commonly used to find leaks during underwater construction. Now Italian officials are investigating how the chemical entered the canal.

The regional environmental service for the state of Venetoincluding Venice confirmed the presence of fluorescein in the canal near the Rialto Bridge and said a full analysis of the water samples would be completed in the coming days.

Yet officials do not know who or what was behind the color.

Luca Zaia, the president of the Veneto region, said further Facebook on Monday that the possibility of copycats was “concerning”.

“Venice, like other iconic places in the Veneto region, has such a high profile that actions like this can ‘attract ‘characters’ seeking publicity,” Mr. Zaia.

It was unclear whether police had identified a suspect and whether anyone could be charged. Venice police did not immediately respond to a request for comment on Tuesday.

Mr Zaia said that “adequate and strong responses are needed.”

“We must protect the city, its monuments, the right of everyone to enjoy its historical treasures free from the traces left by rowdy individuals,” he said.

Fluorescein may have low toxicity; however, it is routinely used in some medical eye exams, according to the U.S. National Library of Medicine. Environmental authorities in Veneto said Monday that tests had not shown toxicity levels in the canal.

Even before tests confirmed fluorescein was in the water, officials believed the chemical caused the abnormal hue based on similar episodes in the past, the environmental agency said in a statement on Sunday.

In 1968, Argentine artist Nicolás García Uriburu colored the Grand Canal green using fluorescein “to draw attention to the relationship between nature and civilization and to promote ecological awareness as an essential part of culture”, according to Argentine artist Nicolás García Uriburu. Metropolitan Museum of Art in New York.

According to the museum, the color faded after about a day. This week, the Veneto environmental agency said that depending on the amount of fluorescein in the water, it could take a few more days for the canal to return to its normal color as the chemical dissolves.

Elisabetta Povoledo And Ilaria Parogni reporting contributed.